Additive material for an electrode of an electrochemical cell, double layer capacitor and production method for such an electrode

A double-layer capacitor comprising:

• two electrodes:
• (i) arranged at a distance from each other, (ii) provided with electrical connections, (iii) separated by a separator, and (iv) wetted by an electrolyte;
• at least one of the electrodes comprising:
• a microporous carbon;
• an active material;
• a conductive additive material in an amount that is in the range of from 2.5 to 15% by weight of the electrode material, said conductive additive material comprising electrically conductive carbon particles having an average particle diameter from 1 to 20 μm and mesopores and macropores defining a three-dimensional pore structure of interconnected pores, wherein pores with a pore diameter of 10 to 1000 nm make up a cumulative pore volume of more than 0.2 cm3/g, and wherein the carbon particles have a microporosity of less than 20% based on a pore volume with pore sizes up to a maximum of 1000 nm, and
• a binder.

A method of producing an electrode for a double-layer capacitor comprising:

• mixing a paste comprising
• starting substances for an active material;
• a conductive additive material in an amount that is in the range of from 2.5 to 15% by weight of the electrode material, said conductive additive material comprising electrically conductive particles of carbon having an average particle diameter from 1 to 20 μm and containing mesopores and macropores forming a three-dimensional pore structure of interconnected pores, wherein pores with a pore diameter of 10 to 1000 nm make up a cumulative pore volume of more than 0.2 cm3/g, and wherein the carbon particles have a microporosity of less than 20% based on a pore volume with pore sizes up to a maximum of 1000 nm, and
• a binder spreading the paste.